Perlish dictionary behavior

[Fred Allen]

Mr. Brewer:

I fruitlessly tried your "thing counter", as you can see below.

class AllThingsStartAtZero(dict): .... def getitem (self, key):
.... return dict.get(self, key, 0)
.... thingCounts = AllThingsStartAtZero()
for thing in ('a','b','c','d','a'): .... thingCounts[thing] += 1
....
Traceback (most recent call last):
File "<interactive input>", line 2, in ?
KeyError: 'a' thingCounts

{}

Reason tells me it should work for me using...

PythonWin 2.3.4 (#53, May 25 2004, 21:17:02) [MSC v.1200 32 bit
(Intel)] on win32.

....as it did for you. The runtime interpreter, however, says
otherwise. Can you see what I've done wrong...I can't?

With thanks in advance, I am,

Respectfully yours,

Fred Allen

[Chris Liechti]

fa****@leveltwo.com (Fred Allen) wrote in
news:72**************************@posting.google.c om:

Mr. Brewer:

I fruitlessly tried your "thing counter", as you can see below.

class AllThingsStartAtZero(dict): ... def getitem (self, key):
it's __getitem__ note the underlines.
... return dict.get(self, key, 0)
... thingCounts = AllThingsStartAtZero()
for thing in ('a','b','c','d','a'): ... thingCounts[thing] += 1
...
Traceback (most recent call last):
File "<interactive input>", line 2, in ?
KeyError: 'a' thingCounts

{}

Reason tells me it should work for me using...

PythonWin 2.3.4 (#53, May 25 2004, 21:17:02) [MSC v.1200 32 bit
(Intel)] on win32.

...as it did for you. The runtime interpreter, however, says
otherwise. Can you see what I've done wrong...I can't?

With thanks in advance, I am,

Respectfully yours,

Fred Allen